Driving mechanism for engine starters



March 6, 1934.

C. T. CUNNIUS DRIVING MECHANISM FOR ENGINE STARTERS Filed Jan. 29, 1932 Ill 26 I N V EN TOR. C44 1///\/ TC 0401005 ATTORNEY,

Patented Mar. 6, 1934 UNITED STATES DRIVING MECHANISM FOR ENGINE STARTERS Calvin '1. Cunnius, Highland Park, N. J., assignor to Eclipse Machine Company, Elmira Heights, N. Y., a corporation of New York Application January 29, 1932, Serial No. 589,547

3 Claims.

My invention relates to starters for internal combustion engines and has for an object to provide an improved driving mechanism therefor.

Another object of the invention is to provide a flexible drive connection between the starting motor and the fly wheel gear, or other operating part of the internal combustion engine.

The invention relates more particularly to that type of starter gear in which a pinion driven by the starting motor is moved by the operation of a pedal or the like into engagement with a gear (such as a fly wheel gear) of the engine. In mechanism of this type the pinion is usually driven through an overrunning roller clutch so as to prevent the engine after it has been started from driving the motor at an excessive speed. Such clutches, after they become worn, are somewhat uncertain in their operation. They may slip and then seize with such suddenness as to break a toothof the pinion or gear.

In a copending application Serial No. 573,364, filed November 6, 1931, I disclose a starter drive in which there is a resilient connection between the clutch and the pinion so as to cushion the drive and prevent damage to the gear. Also a ratchet type of clutch is used in place of the roller type, and inertia means is employed for throwing the clutch members into engagement when the starter motor is energized. In the present application, I disclose a starter drive in which a friction clutch is provided in place of the ratchet clutch, inertia means being employed to effect engagement and disengagement of the friction clutch.

Other objects and advantages of my invention will appear in the following description of a preferred embodiment and thereafter the novelty and scope of the invention will be pointed out in the claims.

In the accompanying drawing;

Figure 1 is a fragmental side elevation partly in longitudinal section and partly in elevation of my improved starter drive; and

Fig. 2 is a view in section taken on the line 2-2 of Fig. 1.

In the drawing part of an internal combustion engine such as a fly wheel gear is indicated in broken lines at 10. This gear is adapted to be engaged by a driving pinion 11 which is journaled upon an outer extension of the armature shaft 12 of an electric starting motor 13. This motor is mounted in a suitable casing 14 which may be conveniently attached to a fixed part of the engine frame (not shown). Secured to the casing 14 is a housing 15 which provides a bearing 16 for the outer end of the shaft 12. Mounted on the armature shaft is a sleeve 17 which has splined engagement with said shaft whereby it may slide freely on the shaft but must rotate I therewith.

The pinion 11 which is freely slidable and rotatable on the shaft 12 carries a cup member 21. The latter is fixed to the pinion and extends toward the motor 13, partly enveloping the sleeve 17. A spiral spring 22 is fitted between the outer end of the sleeve 1'? and the base of the cup 21.

The members 17 and 21 serve as carriers for the driving disks 24 and. the driven disks 25 respectively, of a multiple disk friction clutch. Each disk 24 is formed on its inner periphery with teeth 26 adapted to engage grooves 27 formed in the outer periphery of the sleeve 17. 'Similarly the disks 25 are provided on their outer periphery with teeth 28 which engage slots 29 formed in the cup member 21. Each groove 27 in the sleeve 17 terminates at its outer end in a shoulder 30, and these shoulders serve as stops for the teeth 25 of the adjacent disk 24.

Mounted upon the sleeve 1'7 is a collar 31 provided with a pair of spaced flanges 32 and 33. Between these flanges are fitted rollers 34 mounted respectively on the opposed arms 35 of a yoke lever 36. This lever is pivoted in the housing 15 at 37 and is provided with an outwardly projecting arm 38 to which a pull rod 39 is secured. This rod may extend to a pedal or operating lever (not shown) whereby the lever 36 may be swung upon its pivot 37.

The flange 33 has a cylindrical extension 40 which is slidable within the rim of the cup member 21 and terminates in an abutment 41 adapted to bear against the adjacent disk 24 of the friction clutch. A cap 42 is fitted over and secured to the rim of the cup 21 and is formed with a bore which provides a slide bearing for the cylinder 40.

A pair of diametrically opposed helical slots 43 are cut in the collar 31 and these are engaged by a pair of diametrically opposed screws 44 which are threaded into the sleeve 17. The direction of the helical slots is such that when the shaft 12 is rotated by the motor, the screws 44 will tend to force the collar toward the right as viewed in Fig. 1.

The lever arm 38 is formed with a lug 45 which is adapted to engage a spring-pressed plunger 46 when said arm is swung downward. The plunger 46 projects from a switch box 47 mounted on the housing 14 and within this box suitable switch 1' mechanism is provided whereby on depression of the plunger 46 the motor 13 will be connected to power. Such switch mechanism is common in the art and needs no detailed description here.

In operation, when it is desired to start the englue the rod 39 is pulled thereby forcing the collar 31 toward the right as viewed in Fig. 1. By reason of the screw and slot connection between the collar 31 and the sleeve 17 the latter is also forced toward the right and through the medium of the 9 spring 22 forces the pinion 11 also toward the right, and into engagement with the gear 10. It will be observed that the teeth of the pinion 11 are tapered at their outer ends so that they will readily force their way into mesh with the teeth of the gear 10. If, however, they should happen to jam against the teeth of gear 10 without sliding into mesh with the same, the spring 22 will give while the arm 38 isswung downward until the lug 45 depresses the switch plunger 46. As soon as the motor is thus connected to power the shaft 12 is rotated together with the sleeve 17 splined thereon. Thereupon, owing to inertia of the collar 31, there will be initially a relative movement between the sleeve 17 and the collar 31 in such directionas to screw the collar toward the right, compressing the disks 24 and 25 between'the abutment 41 and the shoulders 30.

This will cause the pinion 11 to rotate with the shaft 12 and, if it is not already in mesh with the gear 10 it will immediately move out of the "jammed position and engage the teeth of gear 10, rotating said gear and starting the engine.

Because the connection between the pinion 11 and the motor is made through a multiple disk friction clutch, the drive will be flexible, preventing any breakage of parts due to sudden starting of the flywheel gear. As soon as the engine starts running the gear 10 will over drive the pinion 11. As a result there will now be relative movement in the opposite sense between the sleeve 17 and the collar 31 which tends to unscrew the collar relieving the pressure of the abutment 41 on the clutch disks. The clutch is thus disengaged and the danger of overdriving the motor is avoided.

While I have described a preferred embodiment of my invention, it will be understood that this is to be taken as illustrative and not limitative and that various changes may be made in form, construction and arrangement of parts without departing from the spirit and scope of my invention as pointed out in the following claims.

I claim:

1. In combination with a starting motor, a pinion movable to and from driving position, means including a friction clutch for operatively connecting the pinion for rotation from said motor, means for moving the pinion to operative position and starting the motor including a yielding splined connection between the clutch and pinion, and inertia controlled means out of the line of transmission of torque, actuated by the acceleration of the motor for throwing the clutch into engagement when the motor is started.

2. In combination with a starting motor, a

driving pinion, a friction clutch comprising a driving member connected to the motor and a driven member connected to the pinion, and inertia controlled means outside the line of trans mission of power actuated by the acceleration of the motor for forcing said members into engagement when the motor is started.

3. In combination with the starting gear of an engine, a pinion movable into and out of mesh with said gear, a motor for driving the pinion, a friction clutch between the motor and the pinion, said clutch being normally disengaged, means operable initially to move the pinion into engagement with said gear and thereafter to start the motor, and inertia means outside the line of transmission of power actuated by the starting of the motor to throw said friction clutch into engagement.

CALVIN T. CUNNIUS. 

